SAN FRANCISCO (CBS SF) — The San Francisco Municipal Transportation Agency on Tuesday approved plans to spend approximately $33.8 million on 45 new hybrid electric buses.

The new 40-foot buses will replace 13-year-old buses currently in service, SFMTA officials said.

If the Board of Supervisors gives the go-ahead, the SFMTA expects to test out a prototype for a month next winter, with all 45 new buses expected to be on the road and in service by summer of 2013, according to the SFMTA.

San Francisco Mayor Ed Lee said investments like the bus purchase will help strengthen the city’s transit system in the long run.

“These new hybrids demonstrate our commitment to a green and clean future for our city’s transit system and will help improve transit times and rider experience,” Lee said in a statement.

SFMTA Director Ed Reiskin said the new fleet will further San Francisco’s “transit first” policy by attracting new riders.

Each of the 45 new buses is estimated to cost about $752,000 and will be paid for with a combination of federal, state and local funds, according to the SFMTA.

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